Field of the Invention
The present invention relates to a vertical lathe configured to perform a cutting process on a workpiece mounted on a turn table for rotating the workpiece, and particularly to an alignment system and method for the vertical lathe which, even when the lathe performs the cutting process on an unbalanced eccentric workpiece, are capable of correcting imbalance automatically and accurately.
Description of the Related Art
In general, as vertical lathes and the like, there is a known vertical lathe configured to rotate a workpiece to be processed, which is mounted on a table, and to perform a cutting process on the rotating workpiece with a tool. Such vertical lathe has a problem that: imbalance occurs depending on the shape of the workpiece; and vibrations thus occur during the process.
Various methods have been proposed to solve the problem with the imbalance.
As documents related to conventional techniques, for example, there are Japanese Patent Application Publications Nos. Hei 2-190732, Hei 6-137985 and Sho 63-34415.
However, the conventional techniques have the following problems because measurement and calculation for correcting the imbalance are very complicated, and because it is difficult to obtain an accurate setting position(s) for the adjustment weight(s):
1. incapability of correcting the imbalance automatically and accurately;
2. constraint on the working area when adjustments are made to an unbalanced workpiece by putting an adjustment weight(s) and the like on the table; and
3. incapability of handling angular misalignment particularly in a case of a direct drive balancer.